Production of dibenzanthrone derivatives and the like



Patented Jan. 10, 1933 UNETED STATES PATENT OFFICE IAN BLOHM ANDERSON, ROBERT FRASER THOMSON, AND JOHN THOMAS, OF GRANGE- MOUTH, SCOTLAND, ASSIGNORS TO SCOTTISH DYES, LIMITED, OF GRANGEMOUTI'I, SCOTLAND PRODUCTION OF DIBENZANTHRONE DERIVATIVES AND THE LIKE No Drawing. Application filed July 6, 1929, Serial No. 376,488, and in Great Britain July 10, 1928.

This invention relates to the production of phenoxy dibenzanthronyl derivatives.

The invention may be carried into effect as indicated by way of illustration in the folo lowing examples, all parts being parts by weight the theoretical. The following gives the structural formula of the product Ewample 1 parts of mono-chlor--Bzl-Bzl-dibenzanthronyl (obtained for example on the chlorinating of Bzl-Bzl-libenzanthronyl with sulphuryl chloride) are mixed with 17 .5 parts of Xylene, 7 parts of finely divided caustic potash and 2 parts of methylated spirit. Mixing is carried out at the ordinary temperat ture and the temperature of the suspension then raised to 80 C. and kept at this for 24: hours. The melt is allowed to cool, the Xylene removed by steam distillation, the residue being boiled and air blown and the bluish-violet suspension filtered off. On drying a violet-black powder is formed dissolving with a red-violet colour in concentrated sulphuric acid changing to a blue on dilution and to violet flocks on continued dilution. The product dyes red-violet shades from a violet vat having a red-brown fluorescence, the shades changing on oxidation in atmosphere to bright reddish-blue. The yield is nearly quantitative.

(Phenoxyh Having now described our invention, what we claim as new and desire to secure by Letters Patent is 1. A process for the production of phenoxy derivatives of dibenzanthrone which consists in heating together phenoXy-Bzl Bzl-dibenzanthronyl, Xylene, caustic potash, and alcohol.

2. A process for producing phenoxy derivatives of dibenzanthrone which consists in heating together 8 parts of phenoXy-Bzl: Bzl-dibenzanthronyl with about parts of Xylene, about 10 parts of caustic potash and about 3 parts of alcohol.

In testimony whereof we have signed our names to this specification.

IAN BLOHM ANDERSON. ROBERT FRASER THOMSON. J. THOMAS.

E wample 2 3 parts of phenoXy-BZl-Bzl-dibenzan- 5 thronyl (prepared for example by treating the chlor-Bzl-Bzl-dibenzanthronyl of EX- aniple 1 with phenol and caustic potash) is treated with 25 parts of Xylene, 10 parts of finely divided caustic potash and 3 parts of alcohol; The product obtained dyes cotton in reddish-violet shades from a red-violet vat changing on oxidation to reddish-blue. It dissolves with a reddish-violet colour in concentrated sulphuric acid changing to blue on dilution. The yield of dyestufi approaches 

